Electric heating unit



May 17, 1949. s. G. OLIVARES y2,470,715

ELECTRICv HEATING UNIT Filed sept. 27, 1946 v 2 sheets-sheet 1 May 17,1949. s, G. @Ln/m55 2,470,715

ELECTRIC HEATING UNIT Filed sept. 2v, 194e 2 sheets-sheet 2 ;Z.Z' 9..Q3. Z8

L I I IEW A I l 'II L M *www Patented May 17, 1949 UNITED STATES PATENTOFFICE ELECTRIC HEATING UNIT Salvador Guillemin Olivares, Mexico City,Mexico Application September 27, 1946, Serial No. 699,680 In MexicoSeptember 27, 1945 1 Claim. 1

This invention relates to a heating unit of high eciency to be usedmainly in electric stoves.

Stoves in present use are provided with heating units ci low eiciency,which due to their design and construction have a useless dispersion ofmore than ity per cent of the thermic energy produced by the electriccurrent. The construction ci these units dees not allow the change ofthe electric resistance used, and their replacement is costly, as itimplies the complete change of the heating unit.

An object of this invention is to provide a highly efficient heatingunit, capable of utilizing almost the total of the electric energy used,through the combination of the diierent emissive powers of the upper andlower plates of the unit.

Another obje-ct of this invention is to provide a heating unit, whichupper plate under optimum conditions has an emissive power representingninety percent of the thermic energy generated by the electricresistance.

A further object oi this invention is to provide a, heating unit, whichmakes possible its installation in the stove, without having to useinsulating devices, as the heat emitted by the lower plate has beenreduced to a minimum.

Another object of this invention is to provide a heating element whichdesign and construction allow a uniform distribution of the therinicenergy produced.

With the ioregoing objects in view, and others which may hereinaftermore fully appear, the invention consists of the novel construction,combination and arrangement of parts, as will be more specicallydescribed and illustrated in the accompanying drawings, wherein areshown embodiments of the invention, but it is to be understood thatchanges, variations and modifications may be resorted to which fallwithin the scope of the invention as claimed.

In the drawings,

Wherein similar reference characters designate similar parts throughoutthe respective views,

Figure 1 is a vertical section of the heating unit, mounted onsupporting brackets and plate.

Figure 2 is a top plan view of the heating unit, partially cut away toshow the resistance.

Figure 3 is a side View of the reflecting annular piece.

Figure 4 is a side view of the heating unit.

Figure 5 is a side view of the supporting plate.

Figure 6 is a bottom plan view of the supporting plate and brackets.

Referring to the drawings, the numeral I, generally designates an upperplate of high emlssive (Cl. 21S-37) 2 power, provided with an outersurface 2, of rough and dull or lusterless nish, to obtain the maximumemission of heat transmitted to said plate by the corresponding heatelement.

Plate I, is xedly joined at its lower portion 3 to the outer portion ofthe upwardly projecting rim 4 of lower plate 5. This lower plate ofequal diameter as upper plate l, has a very low emissive power and it isprovided with an upwardly projecting rim 4, to form a space `(i, wherethe heating element 9 is located.

The outer surface 'I of lower plate 5, is lhighly polished with amirror-like nish, so that its heat emissive power is reduced to aminimum, which may be estimated as ve percent of the total thermieenergy produced by the heating element. The total and effective joint ofthe upwardly projecting rim 4 and the inner portion of plate I, byscrews 8, provides the means for the perfect conduction to upper plateI, of the thermic energy collected by lower plate 5.

In space t, there is a heating element 9, consisting of a resistance 29,made of nichrome wire or tape, or any other suitable material, radiallywound on an insulating disc itl, which fixedly holds it. Said resistanceis placed between two electric insulating discs 3i?, and has two or moreseparate windings, in order to provide different heat intensities in thestove. lThe ends of these resistance windings are connected to terminalsil, held at the center` I2 of supporting disc Iii, and to the stoveselectric circuit by means oi conductors I3, which are tagged with anumber or symbol to allow their correct connection to the circuit, whenthe heating unit is taken apart for cleaning or replacement. Theconstruction of the heating element provides a uniform generation anddistribution of heat in the space formed by the upper and lower plates.

rIhe maximum eiiiciency of this heating unit has lbeen obtained throughthe novel and useful combination of a highly emissive surface in theouter portion oi upper plate i, and a nonemissive surface in the outerportion of lower disc or plate 5. In this manner, heat generated by theheating element, is absorbed in equal proportions by plate I and plate5; plate i, with its rough dull outer surface allows an immediate andtotal emission of heat, while plate 5, with a highly polished outersurface, only emits from three to five percent of the thermic energyabsorbed from the heating element. With plates I and 5, firmly joined atits lower portion and thermic energy transmitted to lower plate 5, is

not accumulated there, but conducted to upper plate l, which highemissive power provides its immediate and eiective dispersion.

Thus practically the total of the thermic energy produced by the heatingelement is emitted by the upper plate, where it is wanted.

The heating unit formed by the upper plate l, lower plate, .and heatingelement 9, is conveniently supported by three or more insulating piecesI5, of substantially spherical form, placed in the circular openings orconcave indentations I6 of supporting plate Il. This supporting plate Ilis provided with a central opening i8, through which a tube I9downwardly extends. Tube i9, is provided with an insulating seal 20,where conductors I3 pass to connectA with terminals H, and it isthreadedly supported at the centerof lower plate 5. At its lower end,tube I,9.is Yprovided with a pair of partial horizontal indentations,where the arms-of a supporting piece 2d --t,keeping the :heatingunitin aiixedv position.

This supporting' piece, isheldon supporting Theassemblyis.convenientlylinstalled in the st0ve,`by means of supportingbrackets 26, which Valsolzeep the unit in a flxe'drposition, engagingstop pieces 521, which downwardly extend from plate. l l.

The 4heat :emission in upper plate il, is 'iurther vincreased byeliminating any ,unwanted lateral dispersions, which ris: accomplished-ibyA an annular reectinggpiece 28, which l reflectsfto Ysaid upperplate, any lateral vheat dispersion Yfrom the peripheryof plates l: andv5.

,Having thus described "my invention, what I .l claim is:

saidsupporting means including a anged disc formedwith spaced openings,spherical heat insulating members seating in said openings and bearingagainstthe lower side of said lower plate `forv supporting the latterspaced from the iiange of saidilanged disc, and radially extendingsupporting arms carried by said anged disc.

SALVADOR GUILLEMIN OLIVARES.

REFERENCES CITED AThe following references are of record in the file ,ofthis patent: 4

UNITED STATESPATENT Number Name Date 1,139,076 Rutenber "May 11, 19151,345,696 Richardson 'July 6, 1920 2,177,173 Da'dson Oct. 24, `1939A2,264,270 Barnsteiner Dec. 2,1941 '2,372,270 Happe "Main 27, 1945123100,672 Wiegand May 2l, 1946

